Forward and reverse gearing for tractors



April 17, 1951 S|ANG.KAN w 2,549,715

FORWARD AND REVERSE GEARING FOR TRACTORS Filed Nov. 18, 1947 sSheets-Sheet 1 I n venlor April 1951 K. SlANG-KAN wu 2,549,715

FORWARD AND REVERSE GEARING FOR TRACTORS Filed Nov. 18, 1947 3Sheets-Sheet 2 Kenneth Siang-Kan Wu April 17, 1951 Filed Nov. 18, 1947K. SlANG-KAN WU FORWARD AND REVERSE GEARING FOR TRACTORS 3 Sheets-Sheet5 [8 Fig.3

z 1- I [I11 2 25 20/7 l0 3 2o /6\g 25 0' Inventor Kenneth Siang-Kan WuWWW 520M23 Patented Apr. 17, 1951 Y OFFICE FORWARD AND REVERSE GEARINGFOR TRACTQRS Kenneth Siang-Kan Wu, Ames, Iowa ApplicationNovember 18,1947,. Serial-No. 786,617

My invention relates to improvements in farm tractors of the typeprovided with a rear end drawbar for towing agricultural implements.

The primary object of my invention is to equip tractors of the typeabove indicated for two-way driving whereby the same may be drivenforwardly rear end foremost to push agricultural implements attached tothe drawbar, or, driven in the usual manner to pull such implements, allwith the driver facing in the direction of travel of the tractor andwith steering means before the driver.

Another object is to accomplish the above by simple means and withoutmaterially adding to the cost of manufacture Of such tractors, or to theupkeep thereof.

Other and subordinate objects, within the'purview of my invention,together with the precise nature of my improvements will be readilyunderstood when the succeeding description and claims are read withreference to the drawings accompanying and forming partof thisspecification.

In said drawings: V Figure 1 is a view in side elevation, partly brokenaway and shown in section, of a farm tractor equipped according to myinvention in a preferred embodiment thereof;

Figure 2 is a view in plan; H

Figure 3 is a fragmentary view in horizontal section taken on the line33 of Figure 1;

Figure 4-is a fragmentary view in vertical longitudinal section taken onthe line 44 of Figure 3;

Figure 5 is a fragmentary view in vertical section taken on the line 5-5of Figure 2;

Figure 6 is a view in transverse section taken on the line 66 of Figure4;

Figure 7 is a view in vertical transverse sectio taken on the line ofFigure 1,

Referring to the drawings by numerals, my improvements have been showntherein as forming part of the equipment of a well-knowntype of farmtractor conventionally illustrated-, as sufficient for the presentpurposes, the numeral 2 designating the chassis, 3 the power plant, 4the dual front steering wheels, 5 the rear driving wheels, 6 the usualsteering wheel, I the drawbar mechanism, and 8 the usual gearshiftlever. As is well-'known,'such tractors are driven by a rear wheeldrive including a power shaft 9-driving a differential in on atransversely split differential drive shaft journalled transversely in adifferential drive housing I2 and provided adjacent opposite endsthereof with a pair of driving gears l3 fastened thereon.

2 Claims, (01. 74 3s5) According to my invention, the usual separaterear axles I4 for the rear drive wheels 5, and which extend through andare suitably journalled in the usual axle housings 5 and in thedifferential drive housing |2 are equipped with a pair of driven gearsl6 fast thereon and spaced rearwardly from the driving gears l3, saidgears l3, l6 forming co-planar pairs and all of said gears l3, l6 beingof the same diameter.

Intermediate the pairs of driving and driven gears 3, l5, within thedifferential drive housing l2 and above the axes of said gears is atransverse, sectional rock shaft IT journalled at its ends in bearingsl8 vertically slidable in guide slots I9 formed in opposite sides of thedifferential drive housing l2. The rock shaft I! is also journalled inbearings 20 on the lower ends of a pair of hanger rods 2| slidablyextending upwardly through guide bosses 22 on top of the differentialdrive housing l2.

Nuts 23 threaded onto the upper ends of said hanger rods 2| for turningagainst said bosses 22 provide for adjusting said hanger rods 2| andsaid rock shaft upwardly.

Coil springs 24 on said hanger rods 2| interposed between the bearings20 and said bosses 22 tension said rods, and said rock shaft 7, againstupward adjustment.

Adjacent each end of the rock shaft I! is a pair of like, meshing,tumbler gears 25 mounted in a yoke 26 to rotate on studs 21 in said yokeequidistantly spaced from the axis of the rock shaft I1.

The yokes 26 are formed as part of the rock shaft I! in two side-by-sideparts, as will be readily understood, which are secured together by thestuds 21. The yokes 2B are arranged parallel on the said rock shaft I1.1

The pairs-of tumbler gears 25 are co-planar with the pairs of drivingand driven gears |3; l6 and "are adapted to be raised and loweredrelative thereto by vertical adjustment of the hanger rods 2| and rockshaft H in a manner'and for a purpose presently described.

' A hand lever 28 fast. on one end of the rock shaft ll provides .forrocking the same into either of two positions, in one of which the pairsof tumbler gears 25 are horizontally aligned in each pair, as shown inFigures 1 and 3', and in the other of which said pairs of gears 25 arevertically aligned in each pair as shown in Figures 4 and 6. A detentsector 29 on one bearing 8, and a detent 30 on said hand lever 28provides for rocking the rock shaft l1 and locking the same in thedifferent positions thereof.

Referring now to the use and operation of my invention as so fardescribed, by adjusting the hanger rods 2| upwardly, through the mediumof the nuts 23, the pairs of tumbler gears 25 may be raised sufficientlyfor the rock shaft 11 to be rocked into either of its two describedpositions. Then, by loosening the nuts 23, the hanger rods 2| and therock shaft 11, will be lowered by the coil springs 24 so that, in thefirst described position of said rock shaft I! with the pairs of tumblergears 25 horizontally aligned in each pair, aid pairs of gears will meshwith and operatively connect the pairs of driving and driven gears l3,16 so that said pair of driven gears 16 will be rotated oppositelyrelative to the driving'gears [3, as indicated by the arrows in Figure1, and the tractor I will be driven forwardly front end foremost in theusual manner. However, in the second described position of the rockshaft 11, with the pairs of tumbler gears 25 vertically aligned in eachpair, said gears will be lowered to mesh the lowermost ears 25 of thepairs with the pairs of driving and driven gears l3, 16 as shown inFigure 4, to operatively connect the driving gears l3 to the drivengears 16 to drive the tractor l forwardly rear end foremost. The meshinggears 25 of said pairs, in this instance, function as reversing gears,that is, as regards the lowermost gears 25, the uppermost gears 25 beingidle.

A drivers seat 3| is provided in the rear of the steering wheel andwhich is pivoted, as at 32, on a seat post 33 to swing around and facerearwardly of the tractor l.

A steering wheel 34, for steering when the tractor I i being driven rearend foremost, is provided in rear of the seat post 33 and which is faston a worm shaft 35 journalled in a worm housing 36 on the upper end of ahollow steering column 37 arising from and suitably fixed to anotherworm housing 38 suitably secured to the rear end of the differentialdrive housing 12.

A worm 39 on the worm shaft 35 meshes with a worm wheel 48 fast on thupper end of a vertical shaft 41 suitably journalled in said column 31.

A Worm 42 fast on the lower end of said shaft 4| and in said housing 38meshes with a worm wheel 43 on one end of a horizontal shaft 44journalled in and extending out of said housing 38 at one side of thetractor l.

A crank arm 45 fast on said shaft 4| is operatively connected by a rod46, extending alongside the tractor I, to a crank arm 41 and the fork 48of the dual front steering wheels 4.

As will be understood, operation of the steering wheel 34 through thedescribed connection to the fork 48 of the dual front steering wheel 4serves to steer the tractor lfrom the rear .end thereof when saidtractor is travelling rear end foremost.

The foregoing will, it is believed, suffice to impart a clearunderstanding of my invention, without further explanation.

Manifestly, the invention, as described, is susceptible of modification,without departing from the inventive concept, and right is hereinreserved to such modifications as fall within the scope of the appendedclaims.

Having described the invention what is claimed as new is:

1. In a tractor having a pair of rear tractor 4 wheels fast on separatealigned axles, a power drive for said axles including a pair oflaterally spaced driving gears, a pair of driven gears fast on saidaxles and forming with said driving gears pairs spaced apart andco-planar in each pair, a pair of meshing tumbler gears associated witheach pair of driving and driven gears, a rock shaft for revolving thepairs of tumbler gears into either of two positions in one of which saidpairs of tumbler gears mesh, respectively, with the gears of theassociated pairs and in the other of which one tumbler gear solely ofeach pair meshes with the pair of associated gears, means for manuallyrocking said shaft, and means for moving said shaft and tumbler gearsaway from said driving and driven gears for revolving of the tumblergears into either position clear of said driving and driven gears, saidmeans being operative to move said shaft and tumbler gears toward thedriving and driven gears in either position of the tumbler gears to meshsaid pairs spaced apart and ;co--planar in each pair,

a pair of meshing tumbler gears associated with each pair of driving anddriven gears, a rock shaft for revolving the pairs of tumbler gears intoeither of two positions in one of which said pairs of tumbler gearsmesh, respectively, with the gears of the associated pairs and in theother of which one tumbler gear solely of each pair meshes with the pairof associated gears, means for manually rocking said shaft, means formoving said shaft and tumbler gears "away from said driving and drivengears for revolvin of the tumbler gears into either position clear ofsaid driving and driven gears, said means being operative to move saidshaft and tumbler gears toward said driving and driven gears'to meshsaid tumbler gears with the driving and driven gears, and means forlocking said shaft against being rocked during movement of the same andsaid tumbler gears away from and toward said driving and driven gears.

KENNETH 'SIANG-KAN WU.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 668,769 Break Feb. 26, 1901829,413 Melo'tte Aug. 28, 1906 1,189,378 Mohr July 4, 1916 1,233,945Wodsedalek July '17, 1917 1,544,775 Plocek July 7, 1925 1,641,802 DanlySept. 6, 1927 1,736,064 Walker Nov. "19, 1929 FOREIGN PATENTS NumberCountry Date 10,290 "Great Britain Apr. 30, 1909 21,944 Great BritainNov. 3, 1914 146,171 Great Britain June 25., 1920

